排序向量對

Question

我正在製作一個撲克評估器，並且我正在使用向量< pair>來存儲數據。現在我被困在排序他們，無論我嘗試我得到編譯器錯誤。

任何幫助表示讚賞，謝謝。

class Histogram { 
private: 
    vector< pair<int,int> > _rankHistogram; 
    vector< pair<int,int> > _suitHistogram; 

    void add(int rank, int suit) { 
     for (int i=0; i < _rankHistogram.size(); i++) 
      if (_rankHistogram[i].first == rank) { _rankHistogram[i].second++; break; } 

     for (int i=0; i < _suitHistogram.size(); i++) 
      if (_suitHistogram[i].first == suit) { _suitHistogram[i].second++; break; } 
    } 
    bool cmp_big_first (pair<int,int> i, pair<int,int> j) { return i.second < j.second; } 

public: 
    Histogram() { 
     _rankHistogram.push_back(make_pair(TWO, 0)); 
     _rankHistogram.push_back(make_pair(THREE, 0)); 
     _rankHistogram.push_back(make_pair(FOUR, 0)); 
     _rankHistogram.push_back(make_pair(FIVE, 0)); 
     _rankHistogram.push_back(make_pair(SIX, 0)); 
     _rankHistogram.push_back(make_pair(SEVEN, 0)); 
     _rankHistogram.push_back(make_pair(EIGHT, 0)); 
     _rankHistogram.push_back(make_pair(NINE, 0)); 
     _rankHistogram.push_back(make_pair(TEN, 0)); 
     _rankHistogram.push_back(make_pair(JACK, 0)); 
     _rankHistogram.push_back(make_pair(QUEEN, 0)); 
     _rankHistogram.push_back(make_pair(KING, 0)); 
     _rankHistogram.push_back(make_pair(ACE, 0)); 

     _suitHistogram.push_back(make_pair(SPADES, 0)); 
     _suitHistogram.push_back(make_pair(HEARTS, 0)); 
     _suitHistogram.push_back(make_pair(DIAMONDS, 0)); 
     _suitHistogram.push_back(make_pair(CLUBS, 0)); 
    } 

    void operator() (Card &c) { add(c.getRank(), c.getSuit()); } 

    void h_sort() { 
     sort(_rankHistogram.begin(), _rankHistogram.end(), cmp_big_first); 
    } 

    void h_print() { 
     for (int i=0; i<_rankHistogram.size(); i++) { 
      cout << Card::rankToString(_rankHistogram[i].first) << "\t\t" << _rankHistogram[i].second << endl; 
     } 
    } 

Answer 1

你需要使它static cmp_big_first。如果不是靜態的，該方法需要一個隱含的this參數（類類型），這對您的使用沒有意義。